1. Field of the Invention
The present invention pertains to an apparatus for actuation of shift elements with a multi-stage planetary transmission gearing system reducing the drive speed of a separate drive unit, which planetary transmission gearing system driving a shift part which actuates a shift element after a prescribable turning or rotation.
2. Description of the Prior Art
A known apparatus of this type has a planetary drive means or transmission with a high return or reversal play, since on the one hand the annular gear rims of the gear transmission stages are rotatably movably arranged upon a power axis and, on the other hand, the drive movement is introduced indirectly.
With an apparatus of this type disclosed by German Patent 30 11 133, which is employed especially for actuation of control-current end switches or shift controllers, there is provided a multi-stage planetary gear transmission drive reducing the drive speed. The planetary drive has a central shaft or insert axis, which for each step or stage carries an annular gear mounting arranged rotatably moveable on the shaft or insert axis, which annular gear mounting on one side is provided with an inner tooth means and on an opposite side being provided with an external tooth means of smaller diameter. Planetary carriers or supports are arranged rigidly upon the shaft or insert axis, which planetary carriers or supports hold the meshing planets of the planetary transmission gearing system against the inner tooth means of the annular gear ring means. The first drive or transmission stage of the planetary transmission gearing system is driven via a sun gear journalled rotatably moveable upon the shaft or insert axis, which sun gear is connected with a separate drive unit via a drive pinion arranged on a shaft journalled in alignment or overhung. The last drive stage has a rotatably arranged planetary carrier or support on which a hollow cylinder is fastened, that is provided with a cam for actuation of the switching or shift elements. The known apparatus has a larger, grate reversal or return play as a consequence of the hollow gear or annular gear ring means arranged upon the insert axis or shaft and the indirectly introduced drive movement.